Chrome Moly Rings Break In

As we ll see the process is somewhat specific and less than rewarding if you screw it up.

Chrome moly rings break in. Moly rings can be steel. Rings and honing procedures have come a long way since the old cast iron ring days. It is suggested you not. I have a hastings steel moly ring sitting on my desk in front of me right now.

Chrome faced rings were a popular option a few years back but now have also succumbed to progress and are rarely employed in modern performance engines. Recommended cylinder to piston clearance of 0015 thousandths per inch of bore works out to 0035 to 005 thousands. And the aterials typically used are cast iron moly chrome or ceramic. Moly rings do not take 1000 miles to seat.

The problem with many chrome faced rings was they were extremely hard and difficult to break in due to their hardness. What s more they didn t handle detonation very well. The base material and design are the same as used in speed pro plasma moly ring sets only the face coating is changed. But all top rings are cast iron either plain or ductile.

If the block is honed correctly for the rings being used there is little to no ring break in. The face of the top rings in these sets are electroplated with chromium to provide a surface that is resistant to abrasive wear. Prior to plasma molly rings the easiest on the cylinders were cast then molly after that and finally chrome rings that wear real well but are real hard on the cylinder because they are a harder. In fact molybdenum is quite a soft metal relative to other options like chrome nitrided steel chrome nitride pvd etc.

Chrome file fit ring sets are listed by bore diameter and list available over sizes. Moly has a very high resistance to scuff. The problem with many chrome facings was that they were extremely hard and difficult to break in properly and often suffered from flaking or cracking when exposed to detonation. The material that s referred to the ring facing or the portion of the ring that runs against the cylinder wall.

When rings are discussed it usually concerns the top ring only. As far as moly rings go we use these in most street applications and plasma moly for most street strip race applications. This goes way beyond just choosing the right break in oil although that s an excellent start. Chrome has good resistance to scuff but does not exhibit moly s oil retention capabilities.

If you want to go modern than plasma molly rings are the way to go. Most grey cast iron rings specify a 150 to 220 grit with 180 being what we recommend. Molly rings are not as picky and they are easier on the bore than chrome rings.